The invention relates to a press having vertical spring supports for resiliently supporting the die-bearing portion of its frame.
Presses of this type are frequently in the form of high-speed punch presses or high-speed presses performing several hundred to more than two thousand punching operations per minute. Of course, other presses too can be mounted in this manner in order to avoid vibrations. Today, such presses represent a very high level of efficiency, their operation being substantially automated.
In considering how it might be possible to achieve further automation in the feeding and removal of parts, it was found that this mount, which provides very good damping during operation, has disadvantages for these purposes in that, depending on the weight on the machine, its height may differ. Particularly when handling devices are to be used, it is no longer possible to manage with rigid programming of the various positions of these handling devices. It is true that there are robots, as handling devices, which are capable of automatically selecting the relevant position with the aid of sensors, but these are not only relatively expensive but also liable to require repair. Such problems do of course also occur in conventional conveying means but are easier to overcome.
German Offenlegungsschrift 2,740,042 as published Mar. 8, 1979, describes a tool change means for a machine, on which the individual processing steps are effected by means of independent tool inserts which are also fastened independently of one another. There must be separate operation steps for changing each of the individual tool inserts, for the die and for the punch.
In the German Offenlegungsschrift mentioned, height adjustment and locking of the tool changing means is one of the necessary steps in the sequence of movements during a tool-changing process. Once again, adjustment to correspond to various positions of the press which are reached because of being supported by spring force could only be achieved with the aid of sensors or the like.